Comparison of beam simulations with measurements for the LEDA LEBT H/sup +/ beam

The Low-Energy Demonstration Accelerator (LEDA) injector is designed to provide 75-keV, 110-mA, proton beams for the LEDA RFQ. After testing the LEDA injector using a 1.25-MeV, CW RFQ, we shortened the low-energy beam transport (LEBT) to 2.69 m, replaced the first LEBT solenoid with one that has a shorter length but the same focusing power, and installed and operated the LEDA injector in the beam tunnel. In this paper we use the TRACE, SCHAR, and PARMELA computer codes to model the proton beam for the as-installed LEBT and we compare the results of these simulations with the LEBT beam measurements. We use the computer code PARMTEQM to transport the SCHAR- and PARMELA- generated beams through the RFQ so that we can compare the predicted RFQ performance with the measured RFQ performance. For a 100-mA, 0.239-/spl pi/-mm-mrad input beam, PARMTEQM predicts the LEDA RFQ transmission will be 92.2%.